step up (v.)

• accelerate
• accost
• advance
• aggravate
• amplify
• approach
• approximate
• charge
• close
• come
• complicate
• concentrate
• condense
• confront
• consolidate
• deepen
• double
• drive
• electrify
• encounter
• energize
• enhance
• exacerbate
• exaggerate
• galvanize
• generate
• hasten
• heighten
• hurry
• intensify
• magnify
• near
• proximate
• quicken
• race
• ramify
• redouble
• reinforce
• rev
• sharpen
• shock
• short
• short-circuit
• stiffen
• strengthen
• thrust
• triple
• whet